Question

How can we test the presence of protein in the food?

Answer 1

Proteins:

1. Proteins are essential bio-molecules that consist of one or more than one long chains of amino acids.
2. They are large macro molecules, which play an important role in growth and development of the body tissues, therefore they are also known as the body building foods.
3. They are the class of biologically significant compounds that have very high molecular weight.

The following is a simple test that can confirm the presence of proteins in a given sample of food:

Biuret test:

1. The compounds that contain peptide linkage can undergo this test.:
2. Proteins are a polypeptide of amino acids which are linked together by peptide bonds.
3. An alkaline solution of protein is treated with a few drops of aqueous copper sulphate and a bluish violet colour can be obtained.

Note: Formation of a violet colour in the solution confirms the presence of Proteins.